InfoPath Dev

 Hi Everyone,

 I want to take data out of 2 text boxes, and insert parts of it into a 3rd data source.

For example I want to take the first letter of the firstName data source, and take the entire contents of the lastName data source and put it into the thirds data source loginName.

So data would be:

First Name "joe", last name "Blogs"

I want the form to then automatically fill out the loginName data source to make it "jblogs"

I understand that I would need to use the substring, substring before/after functions, but I can't figure out how it is supposed to work.

Can someone hhelp me please.

Thanks in advance.

In this case, I think the formula you want is:

concat(substring(firstName, 1, 1), ' ', lastName))